Wound healing is a complex regeneration process, which is characterized by degradation and re-assembly of connective tissue and epidermal layer. The pH value within the wound-milieu influences (directly and indirectly) all biochemical reactions taking place in this process of healing. Interestingly, it is so far a neglected parameter for the overall outcome.
For more than three decades the common assumption amongst physicians was that a low pH value, such as it is found on normal skin, is favorable for wound healing. However, investigations have shown that some healing processes, such as the take-rate of skin-grafts, actually require an alkaline milieu. The matter is thus much more complicated than was previously assumed.
One review suggests that wound pH is a potent influential factor for the healing process and that different pH ranges are required for certain distinct phases of wound healing (L. Schneider et al., Influence of pH on wound-healing: a new perspective for wound-therapy? Arch Dermatol. Res. 298: 413-420 (2007)). Further systematic data needs to be collected for a better understanding of the pH requirements under specific circumstances. This may be important as it may help to develop new pH targeted therapeutic strategies.
Another common agent used in wound treatments is hydrogen peroxide. It has been hypothesized that hydrogen peroxide would accelerate reepithelization and/or have a positive effect on infection. Unfortunately, the results of using hydrogen peroxide alone do not appear to support this hypothesis.
One report using a combination of baking soda and hydrogen peroxide on post-surgical wound healing showed a significant increase in wound healing from oral surgery (A. Dentino et al., Effect of a baking soda-peroxide dentifrice on post-surgical wound healing, American Journal of Dentistry 8(3): 125-7 (1995)). In this report the effects of twice daily brushing with a baking soda-hydrogen peroxide dentifrice or a placebo dentifrice were observed over a 28-day post-surgical period. At days 7 and 14, soft tissue appearance/wound healing (STA) was assessed based on color and edema. Post-surgical wound healing was statistically significantly improved at day 7 with the trend continuing to day 14 when sodium bicarbonate-hydrogen peroxide was used as compared to a control. Such materials were shown to be a possibly effective aid in the early phase of healing following gingival flap surgery. However, the compositions used were designed for oral surgery, and were not adapted to other forms of treatment. Accordingly, there is a need for new compositions and methods for treating wounds.